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| 1 | Meta分析研究设计中的PICOS原则显示文摘Meta分析是利用高质量的一级文献进行合并分析从而认识临床问题的重要循证方法。为了获得高质量的研究结果服务临床,在科学问题的构建过程中,通常依靠PICOS原则帮助完成研究设计。如同很多重要的原则,PICOS来自多个研究要素的缩写,含义如下。 | 李雪迎 | 2016 | 中国介入心脏病学杂志2016，24，11： | 30 |
| 2 | Potentially dangerous glacial lakes across the Tibetan Plateau revealed using a large-scale automated assessment approach显示文摘Glacial lake outburst floods(GLOFs) are a major concern in the Himalaya and on the Tibetan Plateau(TP),where several disasters occurring over the past century have caused significant loss of life and damage to infrastructure. This study responds directly to the needs of local authorities to provide guidance on the most dangerous glacial lakes across TP where local monitoring and other risk reduction strategies can subsequently be targeted. Specifically, the study aims to establish a first comprehensive prioritisation ranking of lake danger for TP, considering both the likelihood and possible magnitude of any outburst event(hazard), and the exposure of downstream communities. A composite inventory of 1,291 glacial lakes(>0.1 km^2) was derived from recent remote sensing studies, and a fully automated and object assessment scheme was implemented using customised GIS tools. Based on four core determinates of GLOF hazard(lake size, watershed area, topographic potential for ice/rock avalanching, and dam steepness), the scheme accurately distinguishes the high to very high hazard level of 19 out of 20 lakes that have previously generated GLOFs. Notably, 16% of all glacial lakes threaten human settlements, with a hotspot of GLOF danger identified in the central Himalayan counties of Jilong, Nyalam, and Dingri, where the potential trans-boundary threat to communities located downstream in Nepal is also recognised. The results provide an important and object scientific basis for decision-making, and the methodological approach is ideally suited for replication across other mountainous regions where such first-order studies are lacking. | Simon Keith Allen Guoqing Zhang Weicai Wang TANDong Yao Tobias Bolch | 2019 | Science Bulletin2019，64，7： | 20 |
| 3 | Safety of endoscopic retrograde cholangiopancreatography in pregnancy: Fluoroscopy time and fetal exposure, does it matter?显示文摘AIM: To estimate the fetal radiation exposure using thermoluminescent dosimeters (TLD's) in pregnant patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) and assess its relevance. METHODS: Data on thirty-five therapeutic ERCPs conducted in pregnant patients from 2001 to 2009 were retrieved from a prospective database. Techniques to minimize fluoroscopy time were implemented and the fluoroscopy times captured. TLD's were placed on the mother to estimate the fetal radiation exposure and the results were compared to the maximum allowed dose of radiation to the fetus [0.005 gray (Gy)]. Obstetrics consultations were obtained and the fetus was monitored before and after the ERCP. Fluoroscopy wasperformed at 75 kVp. ERCP was performed with the patients supine by dedicated biliary endoscopists performing more than 500 cases a year. RESULTS: A total of 35 pregnant patients underwent ERCP and biliary sphincterotomy (14 in first trimester, 11 in second trimester, and 10 in third trimester). Mean maternal age was 25 years (range 16-37 years) and mean gestational age was 18.9 wk (range 4-35 wk). Mean fluoroscopy time was 0.15 min (range 0-1 min). For 23 women, the estimated fetal radiation exposure was almost negligible (< 0.0001 Gy) while for 8 women, it was within the 0.0001-0.0002 Gy range. Three women had an estimated fetal radiation exposure between 0.0002 and 0.0005 Gy and 1 woman had an estimated fetal radiation exposure greater than 0.0005 Gy. Complications included 2 post-sphincterotomy bleeds, 2 post-ERCP pancreatitis, and 1 fatal acute respiratory distress syndrome. One patient developed cholecystitis 2 d after ERCP. CONCLUSION: ERCP with modified techniques is safe during pregnancy, and estimating the fetal radiation exposure from the fluoroscopy time or measuring it via TLD's is unnecessary. | Ioana Smith Monica Gaidhane Allen Goode Michel Kahaleh | 2013 | World Journal of Gastrointestinal Endoscopy2013，5，4： | 12 |
| 4 | Acute hepatitis C virus infection in a nurse trainee following a needlestick injury显示文摘Hepatitis C virus(HCV) infection after biological accident(needlestick injury) is a rare event.This report describes the first case of acute HCV infection after a needlestick injury in a female nursing student at Padua University Hospital.The student nurse was injured on the second finger of the right hand when recapping a 23-gauge needle after taking a blood sample.The patient who was the source was a 72-year-old female with weakly positive anti-HCV test results.Three months after the injury,at the second step of followup,a relevant increase in transaminases with a low viral replication activity(350 IU/mL) was observed in the student,indicating HCV infection.The patient tested positive for the same genotype(1b) of HCV as the injured student.A rapid decline in transaminases,which was not accompanied by viral clearance,and persistently positive HCV-RNA was described 1 mo later.Six months after testing positive for HCV,the student was treated with pegylated interferon plus ribavirin for 24 wk.A rapid virological response was observed after 4 wk of treatment,and a sustained virological response(SVR) was evident 6 mo after therapy withdrawal,confirming that the patient was definitively cured.Despite the favourable IL28B gene(rs12979860) CC-polymorphism observed in the patient,which is usually predictive of a spontaneous clearance and SVR,spontaneous viral clearance did not take place;however,infection with this genotype was promising for a sustained virological response after therapy. | Renzo Scaggiante Liliana Chemello Roberto Rinaldi Giovanni Battista Bartolucci Andrea Trevisan | 2013 | World Journal of Gastroenterology2013，19，4： | 11 |
| 5 | Rational design of three-phase interfaces for electrocatalysis显示文摘Gas-involving electrochemical reactions,like oxygen reduction reaction (ORR),oxygen evolution reaction (OER),and hydrogen evolution reaction (HER),are critical processes for energy-saving,environment-friendly energy conversion and storage technologies which gain increasing attention.The development of according electrocatalysts is key to boost their electrocatalytic performances.Dramatic efforts have been put into the development of advanced electrocatalysts to overcome sluggish kinetics.On the other hand,the electrode interfaces-architecture construction plays an equally important role for practical applications because these imperative electrode reactions generally proceed at triple-phase interfaces of gas,liquid electrolyte,and solid electrocatalyst.A desirable architecture should facilitate the complicate reactions occur at the triple-phase interfaces,which including mass diffusion,surface reaction and electron transfer.In this review,we will summarize some design principles and synthetic strategies for optimizing triple-phase interfaces of gas-involving electrocatalysis systematically,based on the electrode reaction process at the three-phase interfaces.It can be divided into three main optimization directions:exposure of active sites,promotion of mass diffusion and acceleration of electron transfer.Furthermore,we especially highlight several remarkable works with comprehensive optimization about specific energy conversion devices,including metal-air batteries,fuel cells,and water-splitting devices are demonstrated with superb efficiency.In the last section,the perspectives and challenges in the future are proposed. | Yuqing Wang Yuqin Zou Li Tao Yanyong Wang Gen Huang Shiqian Du Shuangyin Wang | 2019 | Nano Research2019，12，9： | 10 |
| 6 | Study on bed load transport for uniform sediment in laminar flow显示文摘Previous studies focused on the bed load transport rate for the condition of turbulent flow,while the knowledge of sediment transport in laminar flow is very limited.As an extreme case to reflect the viscous effect on sediment transport,sediment transport in laminar flow is considered in this paper.There are at least two factors affecting the transport rate of sediment under laminar flow conditions: (1) fluid forces;(2) particle to particle interactions.Together,these two factors represent the physical transport system.First,an exposure degree Probability Density Function (PDF) is developed to explore how the transport rate can be associated with characteristics of laminar flow and this factor reflects the particle to particle interactions,and the pickup probability equation in the absence of turbulence is developed based on the stochastic approach which reflects the exposure degree influence.Then,the formulas to calculate the critical shear stress of incipient motion and the bed load transport rate of fine uniform sediment are established.The derivation is made mainly based on Einstein’s bed load theory;we choose Einstein’s equation to model this system because we believe that the probabilistic approach taken is an appropriate way to account for the spatial and temporal variations in the forces causing sediment transport.These formulas have been tested against a wide range of existing laboratory data and compared with other existing empirical or semiempirical methods.The predictions by these newly proposed formulas are very good. | YANG FengGuang,LIU XingNian,CAO ShuYou,YANG KeJun & HUANG Er State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu 610065,China | 2010 | Science China(Technological Sciences)2010，53，9： | 9 |
| 7 | 循证护理问题的构成显示文摘通常,一个理想的循证问题应包括4个要素:研究对象、干预类型或暴露类型、评价的结局和研究的设计类型。目前国际通用的模式为PICO格式。P为特定的人群(population),主要描述什么是目标人群,这类人群需要考虑的特征有哪些;I为干预或暴露(intervention/exposure),主要描述哪些是需要考虑的干预措施或暴露因素,也可能是预后的因素或诊断试验;C为对照组或另一种可用于比较的干预措施(control/comparator);O为结局(outcome),描述感兴趣的结局是什么。 | 胡雁 | 2016 | 中国护理管理2016，16，2： | 9 |
| 8 | The Effect of PCDH15 Gene Variations on the Risk of Noise-induced Hearing Loss in a Chinese Population显示文摘导致噪音的听觉损失(NIHL ) 是在环境、基因的因素之间的相互作用引起的复杂疾病。这研究调查了在 protocadherin 的基因可变性是否联系了 15 (PCDH15 ) 在一张中国人口位于增加的危险性下面到 NIHL 的发展。结果证明与 rs11004085 的 TT 遗传型相比, CT/CC 遗传型与 NIHL 的增加的风险被联系[调整机会比率(或)= 2.64;95% 信心间隔(CI ) :1.14-6.11, P = 0.024 ] 。另外,在 rs11004085 和 rs978842 之间的重要相互作用基因变化和噪音暴露在高级暴露组被观察(P < 0.05 ) 。而且,当与噪音暴露的高水平结合了时,风险 haplotype TAGCC 被观察(P < 0.05 ) 。因此,我们的学习证实在 PCDH15 的基因变化在人修改危险性到 NIHL 开发。 | XU Xiang Rong WANG Jing Jing YANG Qiu Yue JIAO Jie HE Li Hua YU Shan Fa GU Gui Zhen CHEN Guo Shun ZHOU Wen Hui WU Hui LI Yan Hong ZHANG Huan Ling ZHANG Zeng Rui JIN Xian Ning | 2017 | Biomedical and Environmental Sciences2017，30，2： | 9 |
| 9 | Effect of Long-term Thermal Exposure on Microstructure and Stress Rupture Properties of GH3535 Superalloy显示文摘The evolution of microstructure and the stress rupture properties of long term thermally exposed GH3535 alloy have been investigated. It was found that M6 C carbides presented in the solid solution heat treated samples. During long term thermal exposure at 700 C, fine M12 C carbides precipitated preferentially at grain boundaries. These carbides coexisted with the pre-exiting M6 C. The stress rupture life of700 C/1000 h exposed sample under creep testing at 650 C/324 MPa is 93 h. It is much longer than that of the solid solution samples. No noticeable changes could be detected in both the microstructure and stress rupture lives when the samples were exposed for time longer than 1000 h M12 C carbides were found to be beneficial to the creep properties. The cracks initiated at the interface of M6 C carbides and matrix, which led to a lower creep rupture life. | T.Liu J.S.Dong L.Wang Z.J.Li X.T.Zhou L.H.Lou J.Zhang | 2015 | Journal of Materials Science & Technology2015，31，3： | 9 |
| 10 | Can media exposure improve stock price efficiency in China and why?显示文摘The media in China has undergone extensive commercialization to become more market-driven over the last 35 years. Based on a sample of over two million newspaper articles, this study investigates whether the media in China has an incremental impact on stock price efficiency. We find that: as media coverage of a firm increases,(1) its stock price synchronicity decreases;(2)the probability of informed trading of its stock increases; and(3) the extent to which its stock price deviates from random walk decreases. Our interregional analysis over thirty-one provinces/regions within China reveals that the effects of the media on decreasing stock price synchronicity, increasing the probability of informed trading, and reducing stock price deviation from random walk are stronger in regions of weaker institutional development.Our findings suggest that a market-driven media can play the role of compensating for the underdeveloped governance institutions in transitional economies such as China. | Jeong-Bon Kim Zhongbo Yu Hao Zhang | 2016 | China Journal of Accounting Research2016，，2： | 8 |
| 11 | An insight of environmental contamination of arsenic on animal health显示文摘The main threats to human health from heavy metals are associated with exposure to lead,cadmium,mercury and arsenic.Exposure to arsenic is mainly via intake of food and drinking water,food being the most important source in most populations.Although adverse health effects of heavy metals have been known for a long time,exposure to heavy metals continues and is even increasing in some areas.Longterm exposure to arsenic in drinking-water is mainly related to increased risks of skin cancer,but also some other cancers,as well as other skin lesions such as hyperkeratosis and pigmentation changes.Therefore,measures should be taken to reduce arsenic exposure in the general population in order to minimize the risk of adverse health effects.Animal are being exposed to arsenic through contaminated drinking water,feedstuff,grasses,vegetables and different leaves.Arsenic has been the most common causes of inorganic chemical poisoning in farm animals.Although,sub-chronic and chronic exposure of arsenic do not generally reveal external signs or symptoms in farm animals but arsenic(or metabolites)concentrations in blood,hair,hoofs and urine are remained high in animals of arsenic contaminated zones.So it is assumed that concentration of arsenic in blood,urine,hair or milk have been used as biomarkers of arsenic exposure in field animals. | Paramita Mandal | 2017 | Emerging Contaminants2017，3，1： | 8 |
| 12 | Cosmic-ray exposure age of Martian meteorite GRV 99027显示文摘We have determined the concentrations of 10Be and 26Al in GRV 99027 recovered by the 16th Chinese Antarctic expedition team, which are 14.1 ± 0.6 dpm/kg and 67.5 ± 3.4 dpm/kg, respectively. From the concentration of 10Be, we calculate a cosmic-ray exposure age of 4.4 ± 0.6 Ma for GRV 99027. The concentration of 26Al is too high compared to the 10Be exposure age, indicating extra production from solar ray. The exposure ages, petrologic and geochemical characteristics of mantle-derived Martian meteorites GRV 99027, LEW 88516, Y-793605, NWA 1950 and ALHA77005 are very similar, suggesting that these meteorites most probably were ejected from Mars in the same impact event. | D. FABEL R. BROWN S. FREEMAN | 2007 | Science China Earth Sciences2007，50，10： | 8 |
| 13 | Early Warning of Acute Altitude Sickness by Physiological Variables and Noninvasive Cardiovascular Indicators显示文摘Objective To examine if the variations at sea level would be able to predict subsequent susceptibility to acute altitude sickness in subjects upon a rapid ascent to high altitude.Methods One hundred and six Han nationality male individuals were recruited to this research.Dynamic electrocardiogram,treadmill exercise test,echocardiography,routine blood examination and biochemical analysis were performed when subjects at sea level and entering the plateau respectively.Then multiple regression analysis was performed to construct a multiple linear regression equation using the Lake Louise Score as dependent variable to predict the risk factors at sea level related to acute mountain sickness(AMS).Results Approximately 49.05%of the individuals developed AMS.The tricuspid annular plane systolic excursion(22.0+2.66 vs.23.2+3.19 mm,t=l.998,P=0.048)was significantly lower in the AMS group at sea level,while count of eosinophil[(0.264+0.393)×109/L vs.(0.126+0.084)×109/L,t=-2.040,P—0.045],percentage of diflerences exceeding 50 ms between adjacent normal number of intervals(PNN50,9.66%±5.40%vs.6.98%±5.66%,t=-2.229,P=0.028)and heart rate variability triangle index(57.1+16.1 vs.50.6+12.7,t=-2.271,P=0.025)were significantly higher.After acute exposure to high altitude,C-reactive protein(0.098+0.103 vs.0.062+0.045 g/L,t=-2.132,P=0.037),aspartate aminotransferase(19.7+6.7275.17,3±3.95 U/L,t=-2.231,P=0.028)and creatinine(85.1±12.9 vs.77.7±11.2 mmol/L,t=3.162,P=0.002)were significantly higher in the AMS group,while alkaline phosphatase(71.7+18.2 vs.80.6+20.2 U/L,t=2.389,P=0.019),standard deviation of normal-to-normal RR intervals(126.5+35.9 vs.143.3+36.4 ms,t—2.320,P—0.022),ejection time(276.9+50.8 vs.313.8+48.9 ms,t—3.641,P—0.001)and heart rate variability triangle index(37.1+12.9 vs.41.9+11.1,t=2.O2O,P=0.047)were significantly lower.Using the Lake Louise Score as the dependent variable,prediction equation were established to estimate AMS:Lake Louise Score=3.783+0.281Xeosinophil-0.219Xalkaline phosphatase+O.O32XPNN50.Conclusions We elucidated the differences of pl^siological variables as well as noninvasive cardiovascular indicators for subjects after high altitude exposure compared with those at sea level.We also created an acute high altitude reaction early warning equation based on the physiological variables and noninvasive cardiovascular indicators at sea level. | Zongbin Li Chunwei Liu Jun Guo Yajun Shi Yang Li Jinli Wang Jing Wang Yundai Chen | 2020 | Chinese Medical Sciences Journal2020，35，1： | 8 |
| 14 | REVIEW Risk Assessment of the Mycotoxin Ochratoxin A显示文摘Ochratoxin A (OA) is a mycotoxin which has been found to occur in foods of plant origin, in edible animal tissues, as well as in human blood sera and tissues. The ability of OA to move up the food chain is aided by its long half-life in certain edible animal species. In this report, an evaluation of the health risks to Canadians due to the presence of OA in food products is presented. The first part of the report deals with the physicochemical aspects, mycology, laboratory production, analytical methods, and natural occurrence in plant products, animal products, and human tissues. The stability of OA in foods and feeds, the effects of food processing, and the removal from foods and feeds by physicochemical means are also discussed. From these data, the worst case estimate for the daily exposure of Canadians to OA, from the consumption of pork-based food products and cereal foods, is approximately 5 ng OA/kg body wt (mean of eaters) for young children, the highest consumption group on a body weight basis. The second part of the report deals with the metabolic disposition as well as the available toxicity database for OA in laboratory animals, farm animals, and humans. The major target for OA toxicity in all mammalian species tested is the kidney, and endemic nephropathies affecting livestock as well as humans have been attributed to OA. OA is also teratogenic, and in the fetus the major target is the developing central nervous system. Recent studies have provided 'clear evidence' of the carcinogenicity of OA in two rodent species. OA was found to be nonmutagenic in various microbial and mammalian gene mutation assays, but weak genotoxic activity to mammalian cells was noted. In addition, OA was found to suppress immune function. Based on the NTP carcinogenicity study with OA in rats, the estimated tolerable daily intake in humans ranges from 0.2 to 4.2 ng OA/kg body wt, depending on the method of extrapolation used. In view of the toxic properties of OA, it is recommended that exposure to OA be kept to a minimum. In Canada, further monitoring programs are required to better define the overall residue profile of OA in cereal grains, animal feeds, animal food products, and human blood. Such data are required to better assess dietary exposure and to ascertain the need for regulatory controls or other control mechanisms. (c)1989 Academic Press, Inc. | T.KUIPER-GOODMAN P.M.SCOTT | 1989 | Biomedical and Environmental Sciences1989，2，3： | 7 |
| 15 | Behavioral Abnormality along with NMDAR-related CREB Suppression in Rat Hippocampus after Shortwave Exposure显示文摘Objective To estimate the detrimental effects of shortwave exposure on rat hippocampal structure and function and explore the underlying mechanisms. Methods One hundred Wistar rats were randomly divided into four groups(25 rats per group) and exposed to 27 MHz continuous shortwave at a power density of 5, 10, or 30 m W/cm^2 for 6 min once only or underwent sham exposure for the control. The spatial learning and memory, electroencephalogram(EEG), hippocampal structure and Nissl bodies were analysed. Furthermore, the expressions of N-methyl-D-aspartate receptor(NMDAR) subunits(NR1, NR2 A, and NR2 B), c AMP responsive element-binding protein(CREB) and phosphorylated CREB(p-CREB) in hippocampal tissue were analysed on 1, 7, and 14 days after exposure. Results The rats in the 10 and 30 m W/cm^2 groups had poor learning and memory, disrupted EEG oscillations, and injured hippocampal structures, including hippocampal neurons degeneration, mitochondria cavitation and blood capillaries swelling. The Nissl body content was also reduced in the exposure groups. Moreover, the hippocampal tissue in the 30 m W/cm^2 group had increased expressions of NR2 A and NR2 B and decreased levels of CREB and p-CREB. Conclusion Shortwave exposure(27 MHz, with an average power density of 10 and 30 m W/cm^2) impaired rats' spatial learning and memory and caused a series of dose-dependent pathophysiological changes. Moreover, NMDAR-related CREB pathway suppression might be involved in shortwave-induced structural and functional impairments in the rat hippocampus. | YU Chao BAI Yan Xin XU Xin Ping GAO Ya Bing HAO Yan Hui WANG Hui TAN Sheng Zhi LI Wen Chao ZHANG Jing YAO Bin Wei DONG Ji ZHAO Li PENG Rui Yun | 2019 | Biomedical and Environmental Sciences2019，32，3： | 7 |
| 16 | Cosmic-ray exposure histories of two Antarctic meteorites from Chinese collections and the Guangmingshan and Zhuanghe chondrites显示文摘Concentrations of noble gases of two Antarctic meteorites (GRV 98002, 98004) from Chinese collections, and the Guangmingshan and Zhuanghe chondrites were measured. Based on the petrography and mineralogy of these meteorites, and production rates of the cosmogenic nuclides, we calculated cosmic-ray exposure and gas retention ages of the four chondrites. Exposure ages of the four chondrites are 0.052 Ma 0.008 Ma (GRV 98004, H5), 17.0 Ma 2.5 Ma (GRV98002, L5), 3.8 Ma 0.6 Ma (Zhuanghe, H5), and 68.9 Ma 10 Ma (Guangmingshan, H5), respectively. The exposure age of GRV 98004 is the lowest value of Antarctic meteorites reported up to date; while that of Guangmingshan is higher than other Chinese meteorites of H-group. Both GRV 98002 and Zhuanghe have low 4He concentrations, probably due to shock effects or solar heating at orbits with small perihelion distances during cosmic-ray exposure. On the other hand, losses of cosmogenic 3He and 4He are correlated with both GRV 98002 and Guangmingshan. | 王道德 林杨挺 刘小汉 琚宜太 | 2003 | Science China Earth Sciences2003，46，12： | 7 |
| 17 | Influence of microwave treatment on mechanical behaviour of compact basalts under different confining pressures显示文摘The realisation of microwave-induced fracturing of hard rocks has potential signiflcance for microwave-assisted mechanical rock fracturing and stress release in deep rock masses.In this context,compact basalts were treated by microwave heating in a multi-mode cavity at a frequency of 2450 MHz,and then,we investigated the mechanical behaviour of basalt samples after microwave treatment under uniaxial compression and conventional triaxial compression(CTC)tests.After microwave exposure,cracks appeared on the surface and inside of the rock sample,and the temperature of the sample's surface was unevenly distributed.The results show that the conventional triaxial compressive strength(CTCS)of basalt samples decreased linearly with microwave exposure time,and the higher the confining pressure,the smaller the reduction in the strength of basalt samples after microwave treatment.Under uniaxial compression,microwave exposure greatly affected the axial deformation,suggesting that deformation resistance of the samples gradually decreases with increasing microwave exposure time.Under triaxial compression,some microcracks induced by microwave exposure closed due to the effect of confining pressure,resulting in the confining pressure inhibiting any rightward shift of the axial deformation curve.Furthermore,under uniaxial compression,the elastic modulus and Poisson's ratio of basalts also decreased in a quasi-linear manner with elapsed microwave exposure time.Under triaxial compression,microwave exposure has slight influence on elastic modulus and Poisson's ratio.After microwave treatment,the changes in rock strength and deformation mainly result from changes in between the mineral structures.Confining pressure results in the closure of microcracks produced by microwave exposure,so that effects of microwave treatment on strength and deformation decrease,thus reducing the influence on elastic constants.The cohesion decreases with increasing microwave exposure time and shows an approximately linear decrease over time.In the basalt samples,new microcracks in various directions generated by microwave exposure can increase the discreteness of test results,while the discreteness of test results caused by microcracks gradually reduces with increasing confining pressure. | Gaoming Lu Xiating Feng Yuanhui Li Xiwei Zhang | 2020 | Journal of Rock Mechanics and Geotechnical Engineering2020，12，2： | 7 |
| 18 | Early life exposure to per-and polyfluoroalkyl substances(PFASs):A critical review显示文摘Due to the dynamic developmental processes during pregnancy,infancy,childhood and adolescence,exposure to PFASs is hypothesized to have the most pronounced negative effects during this period.In this review we critically evaluate the current state of the science regarding human early life exposure processes(until 18 years of age)to per-and polyfluoroalkyl substances(PFASs).Efficient placental transfer of perfluoroalkyl acids(PFAAs)results in relatively high prenatal exposure compared with many neutral organic contaminants.The few biomonitoring studies that specifically target infants,toddlers and other children suggest relatively high serum concentrations of perfluorooctane sulfonic acid(PFOS)and perfluorooctanoic acid(PFOA)in early life with peak concentrations occurring sometime before the child reaches 20 months.This peak in serum concentrations is most likely explained by exposure via breastfeeding,ingestion of house dust and/or specific contact events with consumer products leading to high body weight normalized estimated daily intakes(EDIs).Although children have higher EDIs of PFASs than adults,these are not always reflected by higher serum levels of PFASs in children in cross-sectional biomonitoring studies due to the confounding effect of age and birth cohort,and different exposure histories due to production changes.Longitudinal exposure studies measuring internal and external exposure(for multiple pathways and PFASs)at several time points during early life are strongly encouraged to understand temporal changes in exposure of individual children.A better quantitative understanding of early life exposure processes would help to improve the validity of epidemiological studies and allow informed decisions regarding setting of regulatory thresholds and appropriate mitigation actions. | Kerstin Winkens Robin Vestergren Urs Berger Ian TCousins | 2017 | Emerging Contaminants2017，3，2： | 6 |
| 19 | 计算机化自适应测验(CAT)的发展和前景展望(续)显示文摘三、CAT中对的估计(一)MLE(极大似然估计法)假设一个能力水平为θ的被试对n道项目X1,X2,…,Xn作答。θ的估计可以通过使(8)式所示的似然函数最大化的方式来得到。令(?)n为此时所得的θ估计。显然(?)n也是(9)式的极大似然估计。已知在一定的条件下,(?)n符合渐进正态,其均值为θ,方差近似为I-1n((?)n)。目前的CAT设计大多通过递归方式在被试回答一个新的项目之后得到最新的θ估计,并根据信息最大化法抽取下一个项目。 | 张华华 程莹 | 2005 | 考试研究2005，1，2： | 6 |
| 20 | 正加速度暴露时兔血清超敏C反应蛋白的变化与心血管损伤风险预测的关系显示文摘目的 探讨重复正加速度(+Gz)暴露时兔血清超敏C反应蛋白(high-sensitivity C-reactive protein,hs-CRP)的变化与心血管损伤风险预测的关系. 方法 将24只动脉粥样硬化实验兔随机分为对照组和+Gz暴露4周、8周、12周组,每组4只.各组兔实验结束后留取静脉血,测定hs-CRP含量,并用电镜观察兔主动脉组织切片. 结果 +Gz暴露对兔静脉血hs-CRP含量的影响差异有统计学意义(F+Gz(1,23)=22.37,P=0.0001);但暴露时间对兔hs-CRP含量不产生影响(F暴露时间(1,23)=0.82,P=0.4550);+Gz暴露与持续时间之间的交互效应对hs-CRP表达量的影响差异无统计学意义(F+Gz×暴露时间(1,1)=1.10,P=0.3540).主动脉电镜观察结果 也给予支持. 结论 重复、长期+Gz暴露可致兔血清hs-CRP长期处于高水平状态,提示应重视飞行员心血管损伤风险的预测. | 罗惠兰 陈勇胜 耿喜臣 孙津津 李玉茜 | 2010 | 中华航空航天医学杂志2010，21，3： | 6 |
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